pair thecenter; thecenter = (105mm,150mm); vardef instructio( expr rayc ) = draw fullcircle scaled rayc shifted thecenter enddef; beginfig(1); numeric i, u, maxray; u = 1mm; maxray = 85u; for i=30u step 1u until 40u: instructio( i ); endfor; for i=153u step 1u until 165u: instructio( i ); endfor; for i=0 step 90 until 270: draw thecenter--(thecenter+maxray*dir(i)); endfor; endfig; end.